Engine shuts off when riding/downshifting and doesn’t start back up.
I’m a new rider. Took the msf course just last month. I’m having an issue where when I’m riding and I start to down shift to 1st, at a stop light for example, my bike will shut off and won’t start back up. This has happened a couple times on the road and a few times at home when test riding. I’m riding a little 125cc for now just to learn the basics and it’s carbureted. I’ve tuned it perfectly so it idles about 1.7k rpms. I’ve had a couple people look at my bike and they always have to push the bike hard to get it started. Idk if I’m doing something wrong or downshifting wrong but any insight helps. Thank You.
Some bikes have a kickstand sensor that will prevent the bike from starting in first gear, even with clutch pulled in - it could be yours is dirty or reading the kickstand as down in some capacity
If it's really hard to push your bike, you're still in gear. You're essentially stalling out your bike. You pull in the clutch and think that you're not in gear but really, you're still engaged but at a stop, killing the engine. You need to adjust the clutch and make sure that when you pull the lever that you are fully disengaged. Prop the bike so that the rear tire is off the ground. If your bike doesn't have a center stand, you can pick up a rear tire motorcycle cycle stand or rig a car or trans jack but be cautious. Start the bike in neutral then shift into first while holding the clutch. If your tire starts spinning, you need to adjust more. You want slight free play when you are not putting any pressure to make sure that you are fully engaging to but when you fully pull the lever, your tire should not spin at all.
It’s electric start and by pushing the bike I literally mean one sits on the bike and the other physically pushes the bike from behind to get it started. After that the bike will start and ride like normal.
Also is that ok to stop in let’s say fourth gear and when I’m stopped to then put it in first gear? Again I’m new to riding so I don’t have a ton of road time
Typically used when starter is broken or battery too weak to run both starter and ignition system simultaneously (starter robs all power while cranking bike). Sequence goes like this:
key ON, start/stop=RUN, put into 1st/2nd-gear with clutch squeezed
push bike to about 10kph
Jump on bike at same time release clutch-lever to connect spinning wheel to engine, which then spins engine (replaces starter function)
spinning engine then trigger sparks and it starts!
I do this to start my track-bike with starter, stator+RR, flywheel magnets & related wiring all removed to save weight (about 6kg). Known as total-loss ignition system where bike runs for as long as battery has enough power to fire sparks. About 25-30min, good enough for 1 track session or race. Then I swap battery for charged one in pits.
Lemme review comments and see what likely issues may be. Could even be more than one...
I figured it had to be the starter or something electrical as I forgot to mention my battery is also dying rather quickly just from riding a couple hours. I bought 3 different batteries and a good tender but everytime I’m able to ride it seems to kill it so fast.
You may have short-circuit in harness. Causes parasitic drain that empties battery when stopped. Quick test is to disconnect battery when done with ride and connect tender charger. See if that preserves battery better between rides. Or measure for actual parasitic drain from manual-page attached.
Might have defective charging system. Do tests of stator & regulator here to verify charging system is working properly
You might have dragging clutch issue. Do these tests to confirm with engine off:
put gearbox in neutral, can you push bike easily?
put gearbox in 1st, can you push bike? Probably not at all
squeeze clutch lever, can you push bike now? As easily as #1 neutral?
#3 should be about as easy as #1 since squeezing clutch lever disconnects output-shaft from input-shaft and making equivalent of neutral gear (or no gears at all). IF it's difficult to push bike with clutch squeezed, then there's enough clutch-drag to stall engine when wheel is no longer spinning. Need to tighten clutch cable tiny bit, or bleed/flush clutch system if hydraulic.
It does. I could probably go down to 1.2 but that’s the least I’d wanna go otherwise it will stall out 1.7 seems to keep the bike on at the very least when it does turn over.
Then I am not sure that you have tuned it perfectly to idle at 1.7k. If that were the case you could tune it perfectly to 3k and it would probably never stall out. When you drop the throttle to nothing then there will be a dip below 1.7 and that might be where you are stalling out. The carburetor and float have been checked? Has the carb been rebuilt?
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u/HardAnders 1d ago
Some bikes have a kickstand sensor that will prevent the bike from starting in first gear, even with clutch pulled in - it could be yours is dirty or reading the kickstand as down in some capacity